AB1473 HEMOPHAGOCYTIC LYMPHOHISTIOCYTOSIS AMONG ADULTS
Authors: M. Ben Brahim, S. Daada, S. Arfa, M. Wafa, H. Ben Brahim, O. Berriche, S. Hammami, M. Chakroun
Journal: Annals of the Rheumatic Diseases (2023)

<h3>Background</h3> Hemophagocytic Lymphohistiocytosis (HLH) is a rare life-threatening condition resulting from an overstimulation of the immune system leading to a multi-organ damage[1]. This condition can be either primary caused by genetic mutations or secondary triggered by infections, autoimmune diseases or malignancies[1]. <h3>Objectives</h3> We sought to examine the clinical characteristics, underling etiologies, management and outcome of adults patients diagnosed with HLH. <h3>Methods</h3> We performed a multi-center retrospective study in the departments of Internal Medicine and Infectious Diseases in both Fattouma Bourguiba and Taher Sfar University hospitals in Tunisia. We identified 38 patients meeting the HLH-2004 diagnostic criteria. <h3>Results</h3> There were 24 women and 14 men. The male/female sex ratio was 0.58. The mean age was 38 years (range 18-80 years). Eight patients (21%) had underling auto-immune disease: 6 patients had systemic lupus erythematosus, 1 patient had rheumatoid arthritis and 1 patient had idiopathic thrombocytopenic purpura. Five patients (13.5%) had underling malignancy. Among the clinical and biological variable of the HLH criteria, the most common features were fever (100%) followed by elevated ferritin level (94.7%) and cytopenia (84.2%). Triglyceride level was elevated in 76.3% of patients. Hemophgocytosis in bone marrow was found in 35 patients (92.1%). Elevated lactatdshydrogenase was found in 76.3% of cases. The most common underlying etiologies were systemic lupus erythematosus (31%) followed by infections (24%), malignancies (16%) and adult still's disease (13%). In our study, 30 patients (78.9%) underwent intravenous immunoglobulin regimen over 2 days. Twenty-three patients (60.5%) received either intravenous and/or oral steroids. Ethoposide was prescribed in 4 cases. The overall mortality in our study was 39.5%. Twenty-three patients achieved remission with 4 relapsing later. Mean cause of relapses was infections. Patients aged above 65 years and patients with systemic lupus erythematosus had poorer prognosis (<i>p</i>=0.013). Patients with systemic lupus erythematosus achieved remission more likely than other patients (<i>p</i>= 0.021). <h3>Conclusion</h3> HLH is an uncommon but fatal disease. The clinical symptoms are non specific leading to misdiagnosis which is associated with a dismal prognosis. Similarly to the literature a female preponderance was found in our study[1]. Systemic lupus erythematosus was found to be the commonest underling cause of HLH in our population which disagrees with the findings of similar studies who identified malignancy or infections as the principal triggers[1,2]. A combination of intravenous steroids and immunoglobulin infusions was prescribed in 47.3% of patients. This combination was proven to be effective as first line treatment [3]. Despite treatment mortality rates remained high in our populations (39.5%) especially among elderly. <h3>References</h3> [1]Ramos-Casals M, Brito-Zerón P, López-Guillermo A, Khamashta MA, Bosch X. Adult haemophagocytic syndrome. The Lancet. 2014; 383(9927):1503–16. [2]Pandey Y, Atwal D, Konda M, Bimali M, Middleton D, Yarlagadda N, et al. Hemophagocytic lymphohistiocytosis in adults. Proc Bayl Univ Med Cent. 2020; 33(3):326–30. [3]Georgiadou S, Gatselis NK, Stefos A, Zachou K, Makaritsis K, Rigopoulou EI, et al. Efficient management of secondary haemophagocytic lymphohistiocytosis with intravenous steroids and γ-immunoglobulin infusions. World J Clin Cases. 2019; 7(21):3394–406. <h3>Acknowledgements:</h3> NIL. <h3>Disclosure of Interests</h3> None Declared.